There has been proposed the method for forming color images on a thermal transfer image-receiving sheet which is dyeable with a sublimable dye by using a thermal transfer sheet composed of the sublimable dye as a recording material and a substrate on which the sublimable dye is supported. In this method, the dye is heated using a heating means such as a thermal head of a printer and transferred on the image-receiving sheet to obtain the color images. The thus formed images are very clear and excellent in transparency because of the dye used, and are therefore expected to provide high-quality images which are excellent in reproducibility of half tones and gradation. In recent years, there is a demand for thermal transfer image-receiving sheets which are excellent in various properties, in particular, all of of dyeability with dyes, light resistance and releasability.
In the dye receptor layer of some of the thermal transfer image-receiving sheets, polyesters are used from the viewpoint of an excellent dyeability thereof with dyes. The thermal transfer image-receiving sheets using such polyesters are disclosed, for example, in JP 5-238167A, JP 2006-347148A, JP 2004-255880A, JP 2004-256813A and JP 2007-175916A in which the embodiments respectively paying attention to specific alcohol components, etc., are described.